Implementation Experiences in Energy Retrofit of Crude Units Using an Alternative Technology

OK-Solutions is implementing in Asian refineries a newly developed heat integration and retrofit method (HIT; heat integration Transportation model). Pinch Technology (PT) has not been popular with crude unit managers because of its limitations. This methodology is superior when applied to crude units, not only because it avoids several splitting-merging problems that PT suggests for crude units, but also because it offers much better economic performance. We will show an example where these advantages as well as the Pinch Technology problems are highlighted and where the profitability is far larger when HIT is used.

Because most of the crude units are badly integrated (lack of heat exchange area and bad allocation of the existing area), there are very profitable opportunities (15 -25% savings, and ROI > 20%, sometimes close to 40%). One of our examples is a 200,000 bpd unit which exhibited a 25% reduction in energy consumption with a return larger than 30% (the retrofit is underway). Other projects we undertook also exhibit similar profitability.

We will also address other practical issues that we had to deal with: a) retrofit has to be conducted such that several different crudes can be processed, b) fouling, hydraulics and leak issues need attention, b) layout and lack of space to add area was always a problem, c) the use of compact and/or twisted tube exchangers was explored and compact exchangers (Alfa Laval Compablocs in our case) were adopted, not only because of better economics but also because available space would not allow traditional S&T exchangers. We will show how we sorted these problems out in our industrial projects.